(Java)如何将CSV文件的一列映射到另一列的不同类型?

Question

所以对于这个问题，我的函数应该返回出现次数最多的复仇者的前10个列表减少顺序)。
在Avenger类中，它与基本的Person类非常相似，但是没有getter函数，只有表示其名称，性别，外观等的字段。

public class Avenger {
public final String name;
public final int appearances;
public final String gender;
public final int year;
public final String honorary;
public final String[] deaths;
public final String[] returns;
public final String notes;
public Avenger(String name,
int appearances,
String gender,
int year,
String honorary,
String[] deaths,
String[] returns,
String notes) {
this.name = name;
this.appearances = appearances;
this.gender = gender;
this.year = year;
this.honorary = honorary;
this.deaths = deaths;
this.returns = returns;
this.notes = notes;
}
public static Avenger valueOf(String line) {
String[] array = line.split(",");
String name = array[0];
int appearances = Integer.valueOf(array[1]);
String gender = array[2];
int year = Integer.valueOf(array[3]);
String honorary = array[4];
String[] deaths = new String[5];
String[] returns = new String[5];
String notes = array[15];
int index = 5;
int i = 0;
while (index < 15) {
deaths[i] = array[index++];
returns[i] = array[index++];
i++;
}
return new Avenger(name, appearances, gender, year, honorary, deaths, returns, notes);
}
@Override
public String toString() {
return "Avenger [name=" + name + ", appearances=" + appearances + ", gender=" + gender + ", year=" + year
+ ", honorary=" + honorary + ", deaths=" + Arrays.toString(deaths) + ", returns="
+ Arrays.toString(returns) + ", notes=" + notes + "]";
}
}

我的函数正在获取顶部的10 APPEARANCES，并且它返回的数字是正确的。

static Function<Stream<Avenger>, List<String>> getTop10ByAppearances = a -> 
a.map(s -> s.appearances).sorted((x, y) -> y - x).limit(10)
.map(p -> p.toString()).collect(Collectors.toList());

然而，我不需要它来返回数字，我需要它来返回与这些数字对应的NAMES。所以我的问题是，我如何将我在这里拥有的映射到名称，然后返回这些名称的List<String>?

Answer 1

我认为只删除第一个map操作并执行比较就足够了

sorted(Comparator.comparingInt((Avenger x) -> x.appearances).reversed())

然后，你保持你在代码中所做的事情。你限制前10个结果，将每个复仇者映射到他们的名字，最后收集结果。

static Function<Stream<Avenger>, List<String>> getTop10ByAppearances = a ->
a.sorted(Comparator.comparingInt((Avenger x) -> x.appearances).reversed())
.limit(10)
.map(p -> p.name)
.collect(Collectors.toList());